1. Field of the Invention
The present invention relates to an information processing apparatus, an information processing method, and a storage medium, which allow a user to enjoy editing and playing back a content such as an audio content, and more particularly, to an information processing apparatus, an information processing method, and a storage medium, which allow a user to enjoy interactively editing and playing back a content such as an audio content, using a user input device such as a keyboard or a mouse. Still more specifically, the present invention relates to an information processing apparatus, an information processing method, and a storage medium, which have a capability of combining a plurality of contents such as audio contents or other types of contents in response to user inputs given via a user input device such as a keyboard or a mouse thereby allowing a user to enjoy editing and playing back such contents, in particular, to an information processing apparatus, an information processing method, and a storage medium, which have a capability of immediately capturing user inputs given via a user input device and combining a plurality of contents such as audio contents or other types of contents in response to the user inputs thereby allowing a user to enjoy editing and playing back such contents.
2. Description of the Related Art
As a result of advances in semiconductor technology and information technology in recent years, personal computers (PCs) and inexpensive high-performance computer systems called work stations (WSs) have become very popular. Various kinds of applications can be executed in a computer environment provided by such a computer system in conjunction with an operating system (OS).
An extremely wide variety of applications can be executed on a computer system. Some examples are a word processor, a spreadsheet, a database, a communication program, and a graphics program. A computer system having high computer power or having a high-performance graphics accelerator can easily create and display a high-reality 2D or 3D graphics image and perform an image conversion on such a graphics image. Using a computer system, it is also possible to editing an audio content by combining a plurality of sound elements, applying an effect (sound effect) to a sound element, and/or time-sequentially arranging sound elements. A user can enjoy playing back an edited audio content. Furthermore, when an audio content is played back, an image (a motion image or a still image) can be displayed in synchronization with the audio content. This provides enhanced visual effects.
A process of editing or playing back an audio content on a computer system such as a personal computer (PC) is discussed in detail below.
An audio content may include a plurality of performance layers of sound elements such as a “sound pattern” and a “one-shot pattern” such as a percussion or a chant and an “effect” for applying a sound effect such as a delay or an echo to sound elements. A new audio content can be created by simultaneously or time-sequentially combining various sound elements in performance layers and by further time-sequentially arranging the resultant combined sound elements.
A dedicated hardware device such as a DJ (disk jockey) playback device for editing and playing back an audio content is known. Such a dedicated hardware device generally includes analog-type user interfaces, such as a volume label, provided for respective parameters such as sound elements or effects, thereby allowing a user to easily edit and play back an audio content. Furthermore, an operator, i.e., a DJ, can modify or change, in real time, a content being played back by operating an analog switch even in the middle of performance or playback of an audio content.
In contrast, when an audio content is edited using a personal computer, editing is performed using a traditional computer user interface such as a mouse or a keyboard. Such a user interface is of the digital type, and is not necessarily suitable for dealing with an audio content including a plurality of sound elements. To modify or change a sound element or an effect in the middle of performance or playback of music, it is required to capture, with a mouse cursor, a corresponding object on a GUI (Graphical User Interface) screen. This makes it difficult to perform an operation in real time.
To simultaneously apply a plurality of effects to an audio content, it is required to turn on/off all corresponding effect pattern switches by operating them one by one or to perform dragging using the mouse cursor to change parameters of effect patterns. Although such an operation using the GUI is suitable for fine adjustment of a parameter, it is difficult to deal with a content in real time.